Hi, I am trying to use the optimize function to optimize a function. The results I am getting don't agree with what I compute on my own and when I look at the graph of
f(x) = 100 + ((x-10)**2 + (x-10)) * cos(x-10), where -10 <= x <= 10 in gnuplot. I suspect I am making a mistake in the usage of the R optimize function, perhaps someone could point out where? > f<-function(x) 100 + ((x-10)**2 + (x-10)) * cos(x-10) to MAXIMIZE: > result=optimize(f, c(-10,10), lower = -10, upper=10, maximum=TRUE) > result $maximum [1] -2.728743 $objective [1] 247.3284 to MINIMIZE > result=optimize(f, c(-10,10), lower = -10, upper=10, maximum=FALSE) > result $minimum [1] 6.290112 $objective [1] 91.52681 However, I believe the correct values should be minimize: x = -5.838 val= -133.020 maximize: x = -8.957 val= 438.448 Thanks, Esmail This is w/ R version 2.8.1 (2008-12-22) under Ubuntu 9.04 ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.